On the Zend Developer Zone, there's a new article that examines one of the key components to just about any framework out there - the front controller.

Like Action Helpers, which I've discussed in a previous article, Front Controller Plugins in Zend Framework are often considered an esoteric, advanced subject. They are, however, remarkably simple to implement, and provide an easy way to extend the functionality and behavior of your entire web application.

The article (from Matthew Weir O'Phinney) looks at the hooks defined in the controller, like routeStartup and preDispatch, and how to work with the controller to add in/get plugins from it. He provides a two examples too: Application Initialization Plugin and a Caching Plugin.

Michael Girouard has posted his 10,00 foot view of the typical structure of an Model/View/Controller application (and framework) and how a page request is handled:

In my previous article, I announced that I would be documenting the process of developing a simple MVC framework. In this post I will go into a little more detail about each of the specific components of our MVC and will discuss the series of events which occur each time a page loads, otherwise known as the page load scenario.

He talks about how URIs work, the role of mod_rewrite, several of the objects involved (like the Front Controller, Request, Route and View) and how they all fit in with the custom Models, Views and Controllers the user could define.